Three of the men were stabbed to death on New Year’s Eve, a fourth died on New Year’s Day, while a fifth – also stabbed on New Year’s Day – remains in critical condition in hospital. The victims were aged between 17 and 21.

Commander Neil Jerome, of the Met’s Territorial Policing Command, spoke of “small groups” who engaged in “disorder and violence and whose actions have had utterly tragic consequences.”

Jerome added: “It is heart-breaking that, at a time when so many of us are contemplating what lies ahead in 2018, four families are dealing with the grief of losing a loved one to senseless violence and the callous use of knives as lethal weapons.”

Five arrests have been made over one of the stabbings, in Enfield in North London.